"We all know about the gadgets that get showered with constant praise - the icons, the segment leaders, and the game changers. Tech history will never forget the Altair 8800, the Walkman, the BlackBerry, and the iPhone. But people do forget - and quickly - about the devices that failed to change the world: the great ideas doomed by mediocre execution, the gadgets that arrived before the market was really ready, or the technologies that found their stride just as the world was pivoting to something else." I was a heavy user of BeOS, Zip drives, and MiniDisc (I was an MD user up until about 2 years ago). I'm starting to see a pattern here.

What about HP RPN scientific calculators? Completely and utterly brilliant devices. For some bizarre reason HP decided they should be sold for 10x the price of a regular scientific calculator and almsot totally lost the market.